苏州医院氟喹诺酮耐药无乳链球菌gyrA和parC分子特征调查  

Surveillance of molecular characteristics of gyrA and parC among fluoroquinolone resistant Streptococcus agalatiae isolates in Suzhou hospitals

作　　者：戴晓莉[1] 沙茜茜 张宇蔺 陆文香[3] 钟桥[3] 

机构地区：[1]苏州大学附属第二医院检验科,江苏苏州215004 [2]苏州大学医学检验系,江苏苏州215009 [3]南京医科大学附属苏州医院检验科,江苏苏州215002

出　　处：《国际检验医学杂志》2018年第5期517-520,共4页International Journal of Laboratory Medicine

基　　金：南京医科大学校基金面上项目(2015NJMU126)

摘　　要：目的调查苏州地区氟喹诺酮耐药无乳链球菌(GBS)临床分离株gyrA和parC基因的分子特征。方法收集氟喹诺酮耐药GBS菌46株,利用PCR法扩增耐药基因gyrA和parC,并进行基因测序,分析其高频突变位点。结果 gyrA以第81位丝氨酸突变为亮氨酸为主,即gyrA_S81L(TCA→TTA)为主,其突变率高达93.4%(43/46)。parC以第79位丝氨酸突变为酪氨酸和苯丙氨酸为主,即parC_S79Y(TCC→TAC),其突变率为73.9%(34/46);以及parC_S79F(TCC→TTC),其突变率为17.4%(8/46)。基因突变模式汇总分析发现,主要以gyrA_S81L合并parC_S79Y为主,占73.9%(34/46);其次为gyrA_S81L合并parC_S79F,占13.0%(6/46)。结论该地区氟喹诺酮耐药GBS耐药基因主要为gyrA和parC,其主要突变模式为gyrA_S81L合并parC_S79Y和gyrA_S81L合并parC_S79F。Objective To investigate the molecular characteristic of fluoroquinolone resistant Streptococcus agalactiae（GBS）isolates in Suzhou.Methods Totally 46 fluoroquinolone resistant GBS strains were collected,and then subjected into PCR and two resistance genes were sequenced and their high frequency mutation sites,gyrA and parC were analysed.Results Among these isolates,the most frequent gyrA mutation was gyrA_S81 L（TCA→TTA）,which displayed 93.4%（43/46）with substituted at No.81 site of amino acid from Ser to Leu.However,the most frequent parC mutation was mutated at No.79 site of amino acid from Ser to Tyr or Phe,with two mutations parC_S79Y（73.9%,34/46）and parC_S79F（17.4%,8/46）.The analysis showed that the major mutation patterns are gyrA_S81 Lwith parC_S79Y（73.9%,34/46）,gyrA_S81L with parC（13.0%,6/46）.Conclusion The most frequent mutations of fluoroquinolone resistant gene in Suzhou are gyrA and parC and the major mutation patterns are gyrA_S81L/parC_S79Y and gyrA_S81L/parC_S79F.

关 键 词：无乳链球菌 氟喹诺酮 耐药 基因突变 

分 类 号：R446.5[医药卫生—诊断学]